TWI390241B - Antireflective film - Google Patents

Description

Anti-reflection film

The present invention relates to an antireflection film for preventing or reducing reflection.

Anti-reflection film, usually used in CRT, PDP and LCD image display devices, in order to prevent contrast reduction or reflection caused by reflection of external light, it is placed on the outermost surface of the display, using optical interference principle to reduce surface reflection rate.

Moreover, in recent years, there has been an increasing tendency for various displays to be used outdoors. Therefore, it is required to further improve the display quality to more clearly recognize the display image.

In order to satisfy these requirements, Patent Document 1 and Patent Document 2 below disclose that a coating layer containing transparent fine particles is formed on the surface of a transparent substrate, and external light is scattered by the uneven surface.

Further, a known one is a hard coat layer and a low refractive index layer formed of a metal oxide or the like on a transparent substrate surface layer, or an antireflection film of a low refractive index layer such as a single layer of an inorganic compound or an organic fluorine compound. . This antireflection film has an antireflection effect in a wide range of visible light, and is used for bonding to a display surface (see Patent Document 3 below).

The above-mentioned anti-reflection film having a hard coat layer formed of a metal oxide or the like and a low refractive index layer or a low-refractive-index layer forming a single-layer inorganic compound or an organic fluorine compound can be usually obtained by PVD (Physical Vapor) Deposition method (vacuum vapor deposition method, reactive vapor deposition method, ion beam assist method, sputtering method, ion plating method, etc.), A dry coating method such as a CVD (Chemical Vapor Deposition) method is used. Such dry coating methods have limitations in substrate size and are not suitable for continuous production, and high production cost is a disadvantage.

Therefore, the wet coating method (dipping coating method, spin coating method, flow coating method, spray coating method, roll coating method, gravure printing method) can be reduced in cost due to large-area and continuous production. Roll coating method, air doctor coating method, blade coating method, wire doctor coating method, blade coating method, reverse roll method, transfer roll Coating method, small-diameter gravure coating method, cast coating method, kiss coating method, slot orifice coating method, calender coating (calendar) The production of an anti-reflection film by a coating method, a die coating method, or the like is attracting attention.

The means for obtaining the low refractive index layer by the wet coating method can be broadly classified into: 1) a method using a fluorine-containing material having a low refractive index; and 2) providing a void in the layer by air A method of mixing in to lower the refractive index.

Specific examples of the material constituting the low refractive index layer by the above method include a fluorine-containing organic material and low refractive index fine particles, and these materials may be used singly or in combination.

Japanese Unexamined Patent Publication No. Hei No. Hei. No. Hei. No. Hei.

The antireflection layer formed by the methods of the above 1) and 2) has poor alkali resistance and has a problem that the antireflection layer peels off when rubbed with an alkaline lotion or the like.

Further, the antireflection film, the low refractive index layer used for the outermost layer, of course, has a low refractive index and must be less likely to be scratched by scratching or the like. Furthermore, it is not easy to adhere to fingerprints, sebum, sweat, cosmetics, etc. during use, and must be easily wiped off even if attached.

However, the low refractive index layer in the prior art does not fully satisfy the characteristics of refractive index, scratch resistance, and antifouling property. As long as these characteristics are not fully satisfied, practically, they cannot be used for an antireflection film having a low refractive index layer.

The present invention has been made in an effort to solve the above problems of the prior art, and an object of the invention is to provide an antireflection film which is a low refractive index layer having a very low refractive index and which is less likely to cause scratches on the surface of a low refractive index layer by scratching or the like. Moreover, the alkaline lotion and other drugs will not erode the surface thereof, causing the low refractive index layer to be peeled off; further, the object is also to provide an antireflection film which has difficulty in attaching fingerprints, sebum, and on the surface of the low refractive index layer. It is a contamination of sweat, cosmetics, etc., and a low refractive index layer which can be easily wiped off even if it adheres.

In order to solve the above problems, the present invention provides an antireflection film which is formed by sequentially laminating a transparent substrate, a high refractive index layer having a refractive index higher than that of a transparent substrate, and a low refractive index layer having a refractive index lower than that of the high refractive index layer. The low refractive index layer is a cured product of a polymerizable composition containing hollow fine particles, a modified polyfluorene oxide compound, and a second resin component different from the modified polyfluorene oxide compound.

According to the present invention, it is possible to obtain an antireflection film in which the refractive index of the low refractive index layer is extremely low, the surface thereof is not easily scratched by scratching, and is not corroded by the drug and does not peel off; in a better form, Get difficult to attach fingerprints, An anti-reflection film that is easily contaminated even if it is contaminated with sebum, sweat, cosmetics, or the like.

Reference numeral 10 in Fig. 1 denotes an antireflection film of the present invention, and the antireflection film 10 is a transparent substrate 11, a high refractive index layer (hard coat layer) 12 formed on the surface of the transparent substrate 11, and a high refractive index layer. A laminate of the low refractive index layer 15 on the surface of 12.

The reflected light that is reflected by the high refractive index layer 12 and the reflected light that is reflected on the surface of the low refractive index layer 15 is reflected in the external light incident on the antireflection film 10, and is reflected on the surface of the transparent substrate 11. The phase difference is offset so that the reflected light cancels each other and attenuates.

FIG. 2 shows a state in which the antireflection film 10 of the present invention is attached to a surface on which a display image of the display device 5 is attached by a transparent adhesive or the like (not shown). As described above, since the reflected light of the external light is attenuated, the image of the display device 5 can be clearly observed.

The high refractive index layer 12 formed on the transparent substrate 11 is preferably a free radiation curable resin in terms of hardness and durability. The free radiation curable resin is not particularly limited as long as it is used for a high refractive index layer, and can be appropriately selected from those conventionally known.

More specifically, the free radiation curable resin for the high refractive index layer contains a photopolymerizable oligomer, a photopolymerizable monomer, a photopolymerization initiator, and the like.

Here, examples of the photopolymerizable oligomer include a polyester acrylate type, an epoxy acrylate type, an urethane acrylate type, and a polyol acrylate type.

Further, examples of the photopolymerizable monomer include trimethylolpropane (meth) acrylate, hexane diol (meth) acrylate, tripropylene glycol di (meth) acrylate, and diethylene glycol bis (a). Acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol hexa(meth) acrylate, 1,6-hexanediol di(meth) acrylate, neopentyl glycol di(meth) acrylate , octa-ocyanuric acid EO modified di(meth) acrylate, dimethylol tricyclodecane di (meth) acrylate, and the like.

In the present invention, the term "(meth)acrylate" means both an acrylate and a methacrylate.

When the high refractive index layer 12 is formed using the free radiation curable resin containing the photopolymerizable monomer and/or the photopolymerizable oligomer, the refractive index of the high refractive index layer 12 can be made larger than that of the transparent substrate 11 described later. Refractive index. In the present invention, it is preferable to use a (meth) acrylate type or the like as a photopolymerizable oligomer, and the photopolymerizable monomer has a large number of functional groups and can be used for the purpose of improving hardness and durability. Pentaerythritol tetra(meth)acrylate or the like is preferred. These photopolymerizable prepolymers (photopolymerizable monomer, photopolymerizable oligomer) may be used alone or in combination of two or more.

The radiation-hardening type resin may, for example, contain any one selected from the group consisting of acetophenones, benzophenones, α-amyl phthalate, tetramethylammonium thiomethacrylate, and thioxanthone. More than this, as a photopolymerization initiator.

Further, any two or more selected from the group consisting of n-butylamine, triethylamine, and poly-n-butylphosphine may be used in combination as a photosensitizer.

Further, in the case where the high refractive index layer 12 is formed of a thermosetting resin, the composition thereof may be a peroxide, as long as the polymerization initiator is appropriately changed.

The low refractive index layer 15 formed on the high refractive index layer 12 is obtained by containing a modified polyoxyxene compound as a first resin component, a second resin component different from the modified polyoxynitride compound, and hollow A layer formed by hardening a polymerizable composition of fine particles. The polymerizable composition is preferably a free radiation curable resin composition.

The hollow fine particles are particles in which voids are formed in one of the fine particles, for example, in hollow fine silica particles, and the internal voids are covered with cerium oxide. Therefore, the refractive index of the hollow fine particles is smaller than that of the usual non-hollow particles due to the filling of the air inside the void. As an example, the refractive index of the hollow vermiculite particles is relative to the refractive index of ordinary vermiculite particles (=1.46). ≦ 1.45.

Further, the specific gravity of the vermiculite particles is about 2, and the specific gravity of the porous vermiculite particles is about 1.7. The hollow vermiculite particles are lighter than ordinary vermiculite particles or porous vermiculite particles, and have a specific gravity of 1.5 or more and 1.6 or less.

Further, the porous vermiculite particles are formed by aggregating a large number of vermiculite particles, and the gaps (voids) between the vermiculite particles are exposed on the surface. Therefore, when the porous vermiculite particles are added to the matrix, the matrix easily penetrates into the inside of the void. On the other hand, even if the hollow vermiculite particles are added to the matrix, the matrix does not penetrate into the voids inside, and the refractive index of the hollow vermiculite particles does not rise.

Therefore, when hollow fine particles such as hollow vermiculite particles are added to the free radiation curable resin for the low refractive index layer 15, it is possible to reduce the amount of the porous particles and the normal particles of the porous vermiculite particles or the like. The refractive index of the refractive index layer 15 is lowered and can be made lower than the refractive index of the transparent substrate 11.

Further, regardless of whether or not the high refractive index layer 12 contains hollow vermiculite particles or the like When the particles are empty, the content (% by weight) is smaller than that of the low refractive index layer. Thereby, the refractive index of the low refractive index layer 15 can be made lower than the refractive index of the high refractive index layer 12.

That is, since the refractive index of the hollow vermiculite particles is lower than that of the methacrylate polymer, the free radiation curable resin for the high refractive index layer 12 and the polymerizable composition for the low refractive index layer 15 are respectively used. When the main component is (meth) acrylate, the refractive index of the low refractive index layer 15 can be made lower than that of the high refractive index layer 12 by adding hollow vermiculite particles only to the polymerizable composition for the low refractive index layer 15. Refractive index.

Further, examples of the hollow fine particles include inorganic hollow fine particles such as vermiculite or alumina, and organic hollow fine particles such as styrene and acrylic. However, in view of the ease of obtaining the present invention, it is preferable to use hollow vermiculite particles. .

The average particle diameter of the hollow fine particles is preferably 10 nm or more and 200 nm or less, and more preferably 30 nm or more and 60 nm or less.

When the average particle diameter is more than 200 nm, light is scattered on the surface of the low refractive index layer 15 due to Rayleigh scattering, and it is white-like, resulting in a decrease in transparency. Further, if the average particle diameter is less than 10 nm, the hollow fine particles may aggregate.

Further, the hollow fine particles are preferably used for a functional group having a surface which can be polymerized by free radiation.

The functional group on the surface of the hollow fine particles is not particularly limited, and preferably, for example, a (meth)acryl fluorenyl group or a vinyl group can be polymerized with a modified polyoxo compound or a second resin component which will be described later.

Hollow fine particles having such a functional group formed on the surface thereof are coated with a higher affinity with a modified polyoxo compound or a second resin component to be described later. The liquid is uniformly mixed with the modified polyoxo compound or the second resin component. Thus, a low refractive index layer 15 having a uniform film quality can be obtained.

Further, when a hollow fine particle having a functional group formed on its surface is used, the modified polyoxyxene compound or the second resin component is modified when the modified polyoxynitride compound or the second resin component is polymerized by irradiation with free radiation. It reacts with the functional groups on the surface of the hollow fine particles to bond to the surface of the hollow fine particles, and as a result, the mechanical strength of the low refractive index layer can be improved.

On the other hand, since the modified polyfluorene oxide compound can improve the hardness, durability, and antifouling property of the low refractive index layer 15, it is preferred to use the first resin component as the polymerizable composition for the low refractive index layer 15. It is used as a free radiation hardening type resin.

The modified polyoxo compound is represented, for example, by the following chemical formula (1).

The main skeleton has two or more siloxane structures (Si-O) bonded to each other, and in the chemical formula (1), the main skeleton is a polydimethyl methoxy oxane having a methyl group bonded to Si of a siloxane. The number and type of substituents bonded to Si of the alkane are not particularly limited, and the number of substituents bonded to one Si is 0, 1 or 2, and the substituent is in addition to the methyl group. An alkyl group such as a propyl group or a butyl group.

The functional groups Ra and Rb are bonded directly or through other bonds to the oxime structure. When there are two or more functional groups Ra and Rb in the molecule of the modified polyoxo compound, each of the functional groups Ra and Rb may be of the same type. Can also be of different types.

The functional groups Ra and Rb may be reacted with the functional groups Ra, Rb, or with other resin components (for example, the second resin component) by free radiation (more preferably by light irradiation). There is no particular limitation. For example, the functional groups Ra and Rb are a methacryl fluorenyl group, an acryl fluorenyl group or a fluorenyl group.

When an example of a step for producing a modified polyoxymethylene compound is described, the raw material may be, for example, a polyfluorene oxide having one or more hydroxyl groups, and an alkoxy compound having a functional group and an alkoxy group (Fig. 3, The upper part of the reaction formula (1)). In the upper stage of the reaction formula (1), the polyfluorene oxide is a dimethyl polyoxyalkylene having 2 hydroxyl groups (1 = 10 to 14).

The alkoxy compound has a functional group selected from the group consisting of a methacryl fluorenyl group, an acryl fluorenyl group and a fluorenyl group as a functional group. In the upper stage of the reaction formula (1), the alkoxy compound is γ-methylpropenyloxypropyltrimethoxydecane having 3 methoxy groups and methacrylonitrile groups.

In a mixture of polyoxymethylene and an alkoxy compound, if necessary, an additive (for example, hexanol) may be added and heated, and the hydroxyl group of the polyoxygen group reacts with the alkoxy group of the alkoxy compound to cause an alkoxy compound bond. It is agglomerated in polyoxyl.

After the completion of the reaction, as long as the remaining additive, unreacted polyoxygen and unreacted alkoxylate, and by-product (methanol) are removed (for example, under reduced pressure), the reaction formula (1) of FIG. 3 can be obtained. The modified polyoxo compound shown in the next paragraph.

The symbol R in Fig. 3 represents a functional group, and the functional group R is the same as the functional group of the alkoxy compound of the starting material, here a methacryl fluorenyl group.

The symbol m in Fig. 3 indicates the number of the structure of the polyoxane from the raw material, and in the step of reacting the polyoxyxene with the alkoxy compound, the rhodium oxide is polymerized when the raw material polyoxygen is polymerized with each other. The number m of constructions is greater than the number 1 of the decane structure of the feedstock.

When the functional polybasic equivalent is 1630 g/mol or more, the antifouling property of the antireflection film can be improved as described later.

By functional group equivalent is meant the mass of the main backbone M (for example, polydimethyloxane) bonded to each functional group. The label unit g/mol is converted into a functional group 1 mol.

The functional group equivalent of the modified polyoxo compound can be calculated, for example, by the spectral intensity of ¹ H-NMR (proton NMR) obtained by a nuclear magnetic resonance measuring apparatus (NMR).

In ¹ H-NMR, the spectrum intensity of H (for example, H of Si—(CH ₃ ) ₂ ) which is bonded to the oxime structure through C and the C-CH ₃ of the functional group can be determined. The ratio of the spectral intensity of H of H, SH, or H of C=CH ₂ .

In terms of obtaining silicon oxide configured Si- alkoxy (CH _{3) 2} of the spectral intensity of H, and where a functional group of C = CH spectral intensity ratio of H ₂ to make an example described, by spectral intensity ratio can be The ratio of the number of Si—(CH ₃ ) ₂ in the azide structure contained in the measurement sample to the number of C=CH ₂ of the functional group was known.

Since the chemical formula of the siloxane structure and the chemical formula of the functional group are known in advance, the ratio of the number of Si-(CH ₃ ) _{2 and} the number of C=CH ₂ of the functional group can be obtained from the oxirane structure. The ratio (A/B) of the number A of the siloxane structure having a Si—(CH ₃ ) ₂ bond and the number B of the functional groups contained in the measurement sample is known.

Since the molecular weight of one unit of a siloxane structure having a Si—(CH ₃ ) ₂ bond (here, dimethyloxane) is known, the molecular weight per unit is multiplied by the above-mentioned oxime The ratio of the number of structures A to the number of functional groups (A/B) is the mass of the structure of the siloxane having a Si-(CH ₃ ) ₂ bond per unit of functional group (ie, The mass of the main skeleton, the mass obtained by multiplying the mass by the Avogadro number, is the functional group equivalent (g/mol).

For example, focusing on polydimethyl siloxane (chemical transfer near Si-CH ₃ : 0 ppm) and methacryl group (C=CH ₂ : chemical transfer near 4 to 7 ppm), the spectral intensity obtained from each The ratio is calculated as the unit of the mark (g/mol).

For example, the product name "X-22-164" (functional base equivalent: 190 g/mol) and "X-22-164AS" (functional base equivalent: 450 g/mol) manufactured by Shin-Etsu Silicone Co., Ltd. "X-22-164A" (functional group equivalent: 860 g/mol), "X-22-164B" (functional group equivalent: 1630 g/mol), "X-22-164C" (functional group equivalent: 2370 g/mol), " X-22-164E" (functional base equivalent: 3900 g/mol).

The content of the modified polyoxygen compound in the polymerizable composition is preferably 10% by weight or less from the viewpoint of coating uniformity.

The second resin component of the polymerizable composition for the low refractive index layer 15 is a resin component different from the modified polyfluorene oxide compound, and is preferably a free radiation curable resin component. Preferably, 90% by weight or more of the second resin component is a polyfunctional monomer.

Here, the polyfunctional monomer is preferably one having two or more (meth) acrylonitrile groups, and further, a polyfunctional monomer, which is an ester of a polyhydric alcohol and a (meth)acrylic acid. Examples of the body include polyethylene glycol diacrylate, ethylene glycol di(meth)acrylate, 1,4-dicyclohexane diacrylate, pentaerythritol tetra(meth)acrylate, and pentaerythritol III ( Methyl)acrylate, trimethylolpropane tri(meth)acrylate, trimethylolethane tri(meth)acrylate, dipentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate Dipentaerythritol hexa(meth) acrylate, 1,2,3-cyclohexane tetramethacrylate, polyurethane polyacrylate, polyester polyacrylate, and the like.

These polyfunctional monomers may be used alone or in combination of two or more kinds, and may be used in combination with a modified polyoxo compound of the first resin component of the low refractive index layer 15.

It is particularly preferred to use one or both of a difunctional (meth) acrylate of a bifunctional monomer and a tetra(meth) acrylate of a tetrafunctional monomer.

An oligomer such as a polyester acrylate oligomer which is less than 10% by weight of the second resin component may also be used.

In the polymerizable composition for the low refractive index layer 15, the same photopolymerization as that used for the high refractive index layer 12 may be added to the hollow vermiculite particles, the modified polyoxo compound, and the second resin component. Starting agent, light sensitizer.

Further, in the case where the low refractive index layer 15 is formed of a thermosetting resin, the composition thereof can be appropriately changed, and a peroxide is usually used.

The transparent substrate 11 used in the present invention may, for example, be a polyester polymer such as polyethylene terephthalate or polyethylene naphthalate, or diethyl cellulose. And a transparent polymer such as a cellulose polymer such as triethylenesulfonyl cellulose, a polycarbonate polymer, or an acrylic polymer such as polymethyl methacrylate. membrane.

The film thickness of the transparent substrate 11 is not particularly limited, and a film having a film thickness of 30 μm or more and 200 μm or less is usually used.

The method of applying the coating liquid for a high refractive index layer and a low refractive index layer of the present invention is not particularly limited, and examples thereof include a wet coating method (dipping coating method, rotation) which can be reduced in cost. Coating method, flow coating method, spray coating method, roll coating method, gravure printing roll coating method, air knife coating method, blade coating method, wire blade coating method, blade coating method, reverse Coating method, transfer roll coating method, small-diameter gravure coating method, contact coating method, casting coating method, slit pore coating method, calender coating method, die coating method, etc. ).

The coating liquid for a high refractive index layer and the coating liquid for a low refractive index layer are sequentially applied onto the transparent substrate 11, and the coating layer is laminated, and then the coating layer is cured by irradiation with free radiation to obtain a transparent layer. An antireflection film of a high refractive index layer 12 and a low refractive index layer 15 is laminated on the substrate 11. Alternatively, the coating of the coating liquid for a high refractive index layer and the curing of the coating layer by irradiation with free radiation and the coating and coating of the coating liquid for a low refractive index layer are sequentially performed on the transparent substrate 11. The coating layer is cured by irradiation with free radiation to obtain an antireflection film in which the high refractive index layer 12 and the low refractive index layer 15 are sequentially laminated on the transparent substrate 11.

Examples of the free radiation include ultraviolet rays, electron beams, and the like, but are not particularly limited thereto. Further, when the free radiation is irradiated, the ambient atmosphere is not particularly limited, and it can be irradiated in various environmental atmospheres such as an inert gas such as air, nitrogen or argon, and in particular, the high refractive index layer 12 can be made low by a nitrogen atmosphere. The refractive index layer 15 is preferred because it has a good film quality.

Specifically, it will be formed with a high refractive index layer or a low refractive index layer. The transparent substrate of the coating layer is directly transferred into the curing chamber, or the coating layer is dried to remove excess solvent and then transferred to the curing chamber.

In the state in which the internal space of the hardening chamber is isolated from the atmosphere, the nitrogen is supplied to the inside of the hardened chamber, and the inside of the hardened chamber is exhausted to form a nitrogen atmosphere having an oxygen concentration of 1000 ppm or less, while maintaining the nitrogen. In the ambient atmosphere, the free radiation such as ultraviolet rays is irradiated onto the coating layer to be hardened.

The film thickness of the low refractive index layer 15 formed on the high refractive index layer 12 is not particularly limited, and is preferably 50 nm to 200 nm. The surface roughness of the low refractive index layer 15 is not particularly limited, and the average surface roughness thereof is preferably 1.0 nm to 5 nm.

[Examples]

<Example 1>

Dipentaerythritol hexaacrylate, isomeric cyanuric acid EO modified diacrylate, and dihydroxytricyclodecane diacrylate, antimony pentoxide, initiator (1-hydroxy-cyclohexyl-phenyl-ketone) The solution was dissolved in a solvent of isopropyl alcohol to have a solid content of 40% by weight to prepare a coating liquid for a high refractive index layer.

Moreover, the solid content means a substance other than the solvent in the coating liquid, and here, it is a photopolymerizable prepolymer such as dipentaerythritol hexaacrylate, and ruthenium pentoxide and a starter.

This high refractive index layer coating liquid was applied onto the surface of the triacetyl cellulose film (80 μm) of the transparent substrate 11 by a concave plate method to have a dried film thickness of 2 μm in an oven at 80 ° C. After drying for 1 minute and 30 seconds, a 160W high-pressure mercury lamp was irradiated for 3 seconds from a distance of 18 cm, thereby hardening it to form a high refractive index. Layer 12.

In order to form the low refractive index layer 15, the following coating liquid is prepared and formed.

A matrix (second resin component) obtained by mixing a blending ratio of 8% by weight of a polyester acrylate oligomer, 35% by weight of pentaerythritol tetraacrylate, and 57% by weight of polyethylene glycol diacrylate was prepared.

40% by weight of hollow vermiculite particles having an average particle diameter of 60 nm, 8% by weight of an α-hydroxyketone-based initiator, and about 1.5 weight of a modified polyfluorene oxide (functional group equivalent: 3900 g/mol) were prepared. % of a low refractive index coating agent (polymerizable composition).

The low refractive index coating agent was dissolved and dispersed in n-butanol in a solvent to prepare a coating liquid for a low refractive index layer of 3.0% by weight of a solid component (low refractive index coating agent).

The coating liquid for the low refractive index layer was coated on the surface of the high refractive index layer 12 by a concave plate method to have a dried film thickness of 100 nm, and a coating layer was formed, which was dried in an oven at 80 ° C for 1 minute and 30 seconds. Under a nitrogen atmosphere (oxygen concentration: 1000 ppm), the light emitted from the high-pressure mercury lamp was irradiated for 3 seconds at a distance of 18 cm from a high-pressure mercury lamp of 160 W, whereby the coating layer was cured to form the low refractive index layer 15 and was implemented. The anti-reflection film 10 of Example 1.

<Example 2>

In addition to the above embodiment, the content of the hollow vermiculite particles of the low refractive index coating agent was changed from 40% by weight to 50% by weight, and the content of the substrate was changed from 50.5% by weight to 40.5% by weight. The antireflection film of Example 2 was prepared under the same conditions.

<Example 3>

The same as the above embodiment except that the content of the hollow vermiculite particles of the low refractive index coating agent is changed from 40% by weight to 60% by weight, and the content of the substrate is changed from 50.5% by weight to 30.5% by weight. The antireflection film of Example 3 was prepared under the same conditions.

<Example 4>

In addition to the above embodiment, the content of the hollow vermiculite particles of the low refractive index coating agent was changed from 40% by weight to 70% by weight, and the content of the substrate was changed from 50.5% by weight to 20.5% by weight. The antireflection film of Example 4 was prepared under the same conditions.

<Example 5>

An antireflection film of Example 5 was prepared under the same conditions as in Example 2 except that the modified polyoxyn compound was changed from a functional group equivalent of 3,900 g/mol to a functional group equivalent of 1,630 g/mol.

<Example 6>

In addition to the above embodiment, the content of the hollow vermiculite particles of the low refractive index coating agent was changed from 40% by weight to 30% by weight, and the content of the substrate was changed from 50.5% by weight to 60.5% by weight. The antireflection film of Example 6 was prepared under the same conditions.

<Example 7>

An antireflection film of Example 7 was prepared under the same conditions as in Example 2 except that the modified polyoxyn compound was changed from a functional group equivalent of 3,900 g/mol to a functional group equivalent of 190 g/mol.

<Example 8>

In addition to the modified polyoxime compound from the functional group equivalent of 3900g / mol The antireflection film of Example 8 was prepared under the same conditions as in Example 2 except that the functional group equivalent was changed to 450 g/mol.

<Example 9>

An antireflection film of Example 9 was prepared under the same conditions as in Example 2 except that the modified polyoxyn compound was changed from a functional group equivalent of 3,900 g/mol to a functional group equivalent of 860 g/mol.

<Comparative Example 1>

An antireflection film of Comparative Example 1 was prepared under the same conditions as in Example 2 except that the modified polyfluorene oxide compound was not added to the low refractive index coating agent.

<Comparative Example 2>

In addition to changing the content of the hollow vermiculite particles of the low refractive index coating agent from 40% by weight to 80% by weight, the content of the modified polyoxyxene compound is changed from 1.5% by weight to 0, and the content of the matrix is An antireflection film of Comparative Example 2 was produced under the same conditions as in Example 1 except that the ratio was changed from 50.5 wt% to 12 wt%.

Using the antireflection films of Examples 1 to 9 and Comparative Examples 1 and 2, "optical characteristics", "antifouling resistance", "drug resistance", "scratch resistance", and "surface roughness" described below were carried out. Each evaluation test of "degree" and "pencil hardness".

<Optical characteristics (reflectance measurement)>

A black tape is adhered to the coated back surface (the surface of the transparent substrate 11 on the side opposite to the side of the high refractive index layer 12 and the low refractive index layer 15 side), and a spectrophotometer [U-4100: manufactured by Hitachi Hitechnologies Co., Ltd.] is used. Measuring wave The lowest reflectance (%) of the coated surface having an incident angle of 12° of light of 370 nm to 790 nm (the surface on the side of the low refractive index layer 15 where the reflective film 10 is formed).

<Antifouling property (erasability of oily pen)>

The oily handwriting attached to the coated surface was wiped with a non-woven fabric made of cellulose (BEMCOT M-3, manufactured by Asahi Kasei Co., Ltd.), and the ease of erasing was visually judged. The benchmark is as follows:

◎: The oil pen liquid is reversed and not easily attached, and can be completely erased.

○: Oily handwriting can be completely erased.

△: The erased trace of the oily pen remains.

×: Oily handwriting cannot be erased.

<Chemical resistance (1% NaOH aqueous solution)>

The black tape was adhered to the back surface of the coating, and a 1% NaOH aqueous solution was adhered to the coated surface. After standing at room temperature for 30 minutes, the adhered 1% aqueous NaOH solution was wiped off, and the appearance was visually confirmed under a white fluorescent lamp. Change. The benchmark is as follows:

◎: The appearance is completely unchanged.

○: The appearance is almost unchanged.

△: Part of the whitening, or part of it is eroded.

×: Albino or completely eroded.

<Scratch resistance (hardness) test>

Using the steel wool of #0000, the surface of the low refractive index layer 15 was rubbed back and forth 20 times with a load of 250 g/cm ² , and the presence or absence of scratches was visually confirmed. The benchmark is as follows:

◎: Scratches are not recognized on the surface.

○: There are several scratches on the surface.

△: Many scratches were recognized on the surface.

×: A scratch is fully recognized.

<surface roughness>

The average surface roughness (Ra) was measured using an atomic force microscope (AFM) [product name "SPI 3800N", manufactured by Seiko Instruments Co., Ltd.].

<Pencil hardness test>

Using a pencil hardness tester [manufactured by Tester Industries Co., Ltd.], the test was carried out at a load of 750 g to confirm whether or not there was a scratch. The hardness of the pencil is 2H. The benchmark is as follows:

OK: 5 tests were performed on each sample, and scratches or depressions were not recognized in 3 or more of the 5 times.

NG: Five tests were performed on each sample, and three or more of the five times were found to have scratches or depressions.

In the pencil hardness test, the pencil hardness is 2H or more for OK.

The results of the respective evaluation tests described above are shown in Table 1 together with the functional group equivalent of the modified polyoxo compound and the content of the hollow vermiculite particles.

As is apparent from the above Table 1, in Comparative Examples 1 and 2 in which the modified polyfluorene oxide compound was not added to the low refractive index layer, not only the antifouling property was poor, but also the pencil hardness was NG, and the practical use as the antireflection film 10 was not satisfied. Minimum necessary features.

Examples 1 to 9 in which a modified polyfluorene oxide compound was added to the low refractive index layer, the pencil hardness was 2H or more, and the scratch resistance test and the chemical resistance were excellent, and the practically necessary characteristics as an antireflection film were satisfied.

In Examples 1 to 9, in particular, the functional group equivalents were 1630 g/mol or more, and the contents of the hollow vermiculite particles were 40% by weight or more and 70% by weight or less, and Examples 1 to 5 were excellent in each evaluation test. the result of.

Although the properties of the antifouling property and the pencil hardness of Example 6 were excellent, the reflectance was as high as 1.79. Therefore, if the content of the hollow vermiculite particles is more than 30% by weight (more preferably 40% by weight or more), the reflectance (refractive index) can be lowered.

Further, although the optical characteristics, chemical resistance, and the like of Examples 7 to 9 were highly evaluated, the antifouling property was poor. From the above results, it is understood that in addition to excellent optical properties and chemical resistance, in order to obtain high antifouling properties, it is preferred to use a modified polyfluorene oxide having a functional group equivalent of 1630 g/mol or more in the low refractive index layer. .

(industrial availability)

The present invention is applicable to an antireflection film which is disposed on the surface of a display of an image display device such as a CRT, a PDP, or an LCD.

5‧‧‧Display device

10‧‧‧Anti-reflective film

11‧‧‧Transparent substrate

12‧‧‧High refractive index layer

15‧‧‧Low refractive index layer

Figure 1 is a cross-sectional view showing an antireflection film of the present invention.

2 is a view showing a state in which an anti-reflection film is attached to a display device; Sectional view.

Figure 3 is a diagram illustrating the steps used to generate a modified polyoxymethylene compound.

11‧‧‧Transparent substrate

12‧‧‧High refractive index layer

15‧‧‧Low refractive index layer

Claims (14)

An anti-reflection film is sequentially laminated: a transparent substrate; a high refractive index layer having a higher refractive index than the transparent substrate; and a low refractive index layer having a lower refractive index than the high refractive index layer, and the low refractive index layer is included a hollow particle, a modified polyoxyxene compound, and a cured product of a polymerizable composition of the free radiation curable second resin component other than the modified polyoxonium compound; the modified polyoxyxene compound having a repeating unit a main skeleton of two or more oxane structures and a functional group bonded to the main skeleton; a mass of a main skeleton of the modified polyoxynitride compound divided by a molar number of a functional group bonded to the main skeleton The value is 3900 g/mol or more. The antireflection film of claim 1, wherein the hollow fine particles are hollow vermiculite particles. The antireflection film of claim 1, wherein the low refractive index layer is a cured product obtained by irradiation with free radiation. The antireflection film of claim 2, wherein the low refractive index layer is a cured product obtained by irradiation with free radiation. The antireflection film of claim 1, wherein the functional group is selected from the group consisting of a acryl group, a methacryl group, and a thio group. The antireflection film according to any one of the first to fourth aspects of the invention, wherein the content of the hollow fine particles in the polymerizable composition is 40% by weight or more and 70% by weight or less. The antireflection film according to any one of claims 1 to 4, wherein the hollow fine particles have an average particle diameter of 10 nm or more and 200 nm or less. The antireflection film according to any one of claims 1 to 4, wherein the hollow fine particles have a functional group which is polymerized by free radiation on the surface. The antireflection film according to any one of claims 1 to 4, wherein the film thickness of the low refractive index layer is 50 nm or more and 200 nm or less. The antireflection film according to any one of claims 1 to 4, wherein the second resin component contains 90% by weight or more of a polyfunctional (meth) acrylate. The antireflection film according to any one of claims 1 to 4, wherein the content of the modified polyoxosiloxane in the polymerizable composition is 10% by weight or less. The antireflection film according to any one of claims 1 to 4, wherein the surface of the low refractive index layer has an average surface roughness of 1.0 nm or more and 5 nm or less. The antireflection film according to any one of claims 1 to 4, wherein the low refractive index layer is a cured product obtained by curing a free radiation curable polymerizable composition in a nitrogen atmosphere. The antireflection film according to any one of claims 1 to 4, wherein the high refractive index layer has a pencil hardness of 2H or more.